Lipoprotein (a) [Lp(a)], a lipoprotein closely related to LDL, is an independent risk factor for development of heart disease. The levels of Lp(a) are strongly genetically determined and differ between various ethnic groups. Very little is known about the metabolism of Lp(a). We plan to relate the metabolism of Lp(a) VLDL and LDL in healthy humans from three different ethnic groups, Hispanics, African Americans, and Caucasians, using stable isotope methods.